84 FAMILIES OF FLOWERING? PLANTS. 
The two preceding families were formerly united with the true nettles 
in a single family, but under the modern conception of natural affinities 
are considered as distinct groups. 
Some of the plants in this family have strong bast fiber which may 
be utilized like hemp, but aside from this they are of no economic 
value, and many are troublesome weeds. Familiar examples of the 
latter are the various true nettles ((/rtica); the wood nettle ( Urticas- 
trum); and the richweed or clearweed (.1dicea). 
Fic. 69.—The Stinging Nettle (Urtica urens). Original. 
